Anthraquinone dye and process of making same.



UNTTED STATES PATENT OFFICE.

ROBERT E. SCHMIDT AND PAUL TUST, OF ELBERFELD, GERMANY, ASSIGNORS TO FARBENFABRIKEN OF ELBERFELD (30., OF NEYV YORK, N. Y.

ANTHRAQLUINONE DYE AND PROCESS OF MAKING SAME.

SPECIFICATION forming part of Letters Patent No. 675,57 5, dated June 4, 1901. Application filed January 3, 1901. Serial No. 41,939. (Specimens) T aZZ whom, it may concern: of paratoluidin and ten parts of crystallized Be it known that we, ROBERT E. SCHMIDT, boric acid. This resulting mixture is heated doctorofphilosophy,chemist,andPAULTUsT, to about from 150 to 160 centigrade until chemist, (assignors to the FAR-BENFABRIKEN the color of the melt has turned from red to 5 OF ELBERFELD COMPANY, of New Yorlg) reblue. After the reaction mass has been alsiding at Elberfeld, Germany, have invented lowed to cool down to about from 60 to 70 a new and useful Improvement in New Ancentigrade it is poured into an excess of dithraquinone Dyes; and weherebydeclare the lute hydrochloric acid, by means of which opfollowing to be a clear and exact description eration the condensation product separates 60 of our invention. in the shape of dark flakes. Subsequently Our invention relates to the manufacture it is filtered off and washed with water. In of new blue dyestuff sulfonic acids of the anorder to be purified, it is dissolved by hot thracene series from the two 1.4 amidooxywaterand precipitated again by the addition anthraquinone sulfonic acids, which can be of common salt, filtered off, and dried. 65 obtained by treating the so-called alpha and hen dry and pulverized,the new coloring beta nitroanthraquinone sulfonic acids (dematter having in a free state the formula scribed by Claus, see Berichte (Yer Dc'zttschen a VII (1) Chemzschcn GcscZZsc72ctft,Vol. 10, p. 1019) Wlill 7 A J V sulfursesquioxid, 0 Q OH4 CH3 7o Our new process consists in treating the 3 said sulfonic acids of 1.4 amidooxyanthrais a dark-blue powder, which is rather diffiquinone having the formula: cultly soluble in cold and more soluble in hot VII water with a blue color. It is easily soluble C H O in ammonia, in ethyl alcohol, (of ninety per 25 H cent.,) and in acetic acid (of fifty per cent.)

3 with a blue color. By the addition of hydrowith primary aromatic amins-such as anichloric acid to its watery solution the color lin, paratoluridin, xylidin, orthe like -in the of the latter turns redder, and by the addipresence of condensing agents, such as boric tion of ammonia to this acid solution the 3o acid or the like. original blue color is again produced. By

' In this process the hydroxy group is reconcentrated sulfuric acid (of 66 Baum) it placed by an alphylainido radical, with the is dissolved, yielding a violet solution the production of new dyestuff sulfonic acids color of which changes into red on the addi having the following general formula: tion of a small quantity of ice, while on add- 35 NH 1 ing a larger quantity of ice the dyestufi C H O Z sulfonic acid is separated in the shape of a 11 SO H dark precipitate. It dyes unmordanted and p 3 chrome-mordanted wool blue shades fast to (R meaning in this formula an alphyl radilight and to alkalies.

40 cal, such as phenyl, tolyl, Xylyl, or the like.) Having now described our invention and The new dyestuff sulfonic acids thus obin what manner the same is to be performed, tained are in a dry state dark powders which what we claim as new, and desire to secure are soluble in water and in ammonia with by Letters Patent, is-

a blue color. They dye unrnordanted and 1. The process for producing new dyestuifs 45 chrome-mordanted wool fast blue shades. of the anthracenc series, which process con- In carrying out our new process practisists in heating the herein-defined sulfonic cally we can'proceed as follows, the parts beacids of 1.4- amidooxyanthraquinone with ing by weight: Thirty parts of the aboveprimary aromatic amius and then isolating mentioned alpha-sulfonic acid of 1.4 amidothe resulting dyestuif sulfonic acids from the 5o oxyanthraquinone having the above-given reaction mixture, substantially as hereinbeformula are mixed with three hundred parts fore described.

2. The process for producing a new dyestuff of the anthracene series, which process consists in heating the alpha-sulfonic acid .of 1.4

amidooxyanthraqninone with paratoluidin,

and then isolating the resulting dyestuff sul fonic acid from the reaction mixture, substantially as hereinbefore described. v

3. The herein-described new dyestuff sulfonic acids of the an'thraoene series which, when dry and pulverized, are dark powders soluble in water and in ammonia with a blue color, dyeing unmordanted and chrome-mordanted wool fast blue shades, substantially as hereinbefore described.

4. The herein-described new dyestuff sulfonic acid, obtainable from the alpha-sulfonic acid of 1.4 amidooxyanthraquinone and paratoluidin, which dyestufi is, when dry and pulverized, a dark-blue powder being rather difficnltly soluble in cold and more soluble in hot water with a blue color, being easily soluble in ammonia, in ethyl alcohol (of ninety per cent.) and in acetic acid (of fifty per cent.)

with a blue color, the color of its watery solution turning redder by the addition of hydrochloric acid and the original blue color being produced again by addingammonia to the acid solution, being dissolved by concentrated sulfuric acid (of 06 Baum) yielding a violet solution the color of which changes into red on the addition of a small quantity of ice, while on adding a larger quantity of ice the dyestuff sulfonic acid separates in the shape of a dark precipitate, dyeing unmordanted and chrome-mordanted wool blue shades fast to light and to alkalies, substantially as hereinbefore described.

' In testimony whereof we have signed our names in the presence of two subscribing witnesses.

ROBERT E. SCHMIDT. PAUL TUST.

lVitnesses:

OTTO KONIG, J. A. RITTERSHAUS. 

